The present invention is a material composition related to manufactured potting soils and growth mediums. The invention is a growth medium produced from commercial and industrial waste materials, primarily coffee grounds, whose nutritional value to plants is equal or superior to extant commercial potting soils or naturally occurring top soils.
Composting or otherwise recycling waste materials are disclosed in various patents. Willisch (U.S. Pat. No. 4,146,382), discloses a method and apparatus for composting refuse and sewage sludge. Varro (U.S. Pat. No. 4,050,917) discloses a method of composting waste by controlling aeration, pH, moisture content, and temperature during composting. Shinholster (U.S. Pat. No. 4,369,054) discloses a composition of pulped fibers and slag. Drysdale, et al (U.S. Pat. No. 5,192,354) discloses a soil substitute made by composting shredded treebark with quary stone particles and silica sand particles. Pinckard (U.S. Pat. No. 4,164,405) discloses a method for controlling fungi that utilizes aerobically fermented cotton gin waste produced under particular conditions.
Commercially, coffee grounds are produced by any and all retail establishments who brew and serve coffee. The scale of this waste production is difficult to track, as it is extremely scattered and diverse, but statistics compiled by the National Coffee Association indicate that coffee consumption produces 20 billion pounds of coffee grounds per year. Industrially, coffee grounds are produced on a massive scale through various food production processes, such as the making of coffee-flavored candies, ice creams and beverages. The vast majority of these coffee grounds are indiscriminately mixed with other waste materials, discarded, and inevitably landfilled. Once so corrupted, their use value is lost. A very small percentage of coffee grounds are donated to community gardens, municipalities, or nonprofit environmental groups, all of whom combine the material with other organic wastes for the purpose of composting it into useable soil amendments and ground covers.
Coffee grounds have been used as a plant fertilizer, particularly for plants that prefer a higher acid content in their soil, such as roses, azaleas, rhododendrons, tomatoes, and evergreens. However, such random mixing and composting does provide a sufficient methodology for providing a plant growth medium that allows the most advantageous absorption of coffee grounds"" latent nutrients.
It would be advantageous, therefore, if coffee grounds could be mixed with other components in the proper quantities to capitalize on coffee grounds"" latent nutrients (most notably nitrogen, potassium and phosphorus, the three most critical elements to healthy plant life) so that the grounds could become more useful to plants, which is not often the case with crude methods of adding coffee grounds to soil or compost. Moreover, the bulk of coffee grounds produced annually in the United States remains vastly underutilized, so it would be commercially advantageous to prepare a plant growth medium from such coffee grounds.
It also would be economically and environmentally advantageous to find practical applications for many other commercial and industrial byproducts that formerly have been underutilized if not discarded.
In one embodiment, a material produced from composting components is provided which comprises by weight from about 55 to 85% coffee grounds, from about 2 to 20% gypsum (calcium sulfate), from about 2 to 25% wood fines (preferably untreated sawdust, bark fines, and waste portions of woody plants), from about 0.5 to 5% bone meal and/or fish meal, from about 0.5 to 5% of blood meal or about 0.2 to 2% ammonium sulfate, and from about 0.05 to 0.15% magnesium sulfate (Epsom salts). Preferably, each of the components are pulverized, measured, and then mixed to form a homogeneous mixture. The pH of the material is preferably about 5.0 to 7, and reached this pH when the material is fully fermented.
Another embodiment includes from about 55 to 80% coffee grounds, from about 10 to 20% gypsum (calcium sulfate), and from about 5 to 15% wood fines. In another embodiment, the material comprises from about 55 to 75% coffee grounds, from about 2 to 10% gypsum (calcium sulfate), and from about 10 to 25% wood fines. Each of the components are pulverized, measured, and then mixed to form a homogeneous mixture; wherein the pH level of the material is about 5.0 to 7; and wherein the material is fully fermented.
The invention is also directed to a method comprising mixing the components and fermenting the mixture to form a mixture having a pH level of about 5.0 to 7.0. Preferably the components should be pulverized and measured before mixing and to form a homogeneous mixture.
In a preferred embodiment comprising composted coffee grounds, gypsum (calcium sulfate), wood fines, bone meal and/or fish meal, a nitrogen-providing substance, and magnesium sulfate (Epsom salts), the material contains about 100-199 ppm nitrogen, about 20-200 ppm phosphorus, about 80-500 ppm potassium, about 25-300 ppm calcium, about 10-200 ppm magnesium, about 20-200 ppm sulfur, and more preferably at least one element selected from the group consisting of boron, iron, manganese, zinc, and copper in the following preferred amounts: 0.1-2.5 ppm boron, about 15-40 ppm iron, about 2-40 ppm manganese, about 5-30 ppm zinc, and about 2-30 ppm copper.
In an alternative embodiment, a material of the invention produced from composting components comprises by weight about 55 to 85% coffee grounds, about 0.5 to 5% of a nitrogen-providing substance, about 2 to 20% of a calcium-providing substance, about 0.05 to 0.15% of a magnesium-providing substance, about 0.5 to 5% of a phosphorous-providing substance, and about 2 to 25% of a composting accelerator. Preferably, this medium contains about 100-199 ppm nitrogen, about 20-200 ppm phosphorus, about 80-500 ppm potassium, about 25-300 ppm calcium, about 10-200 ppm magnesium, about 20-200 ppm sulfur, and more preferably about 0.1-2.5 ppm boron, about 15-40 ppm iron, about 2-40 ppm manganese, about 5-30 ppm zinc, and about 2-30 ppm copper. A preferred method of making a plant growth medium comprises providing the nitrogen-providing substance, the calcium-providing substance, the magnesium-providing substance, the phosphorous-providing substance, and the composting accelerator, and composting the mixture with coffee grounds to form the plant growth medium.
These embodiments are described below in more detail.